(1) Field of the Invention
This invention relates to a novel pigment composition, and more specifically to a pigment composition which contains as a pigment dispersant or a flushing agent a phosphoric ester compound containing a polyester chain and is useful as a coloring material such as printing ink, paint or synthetic resin colorant.
(2) Description of the Prior Art
In the production of paints and printing inks, lecithin, a phospholipid, has heretofore been used by way of example as a dispersant or a flushing agent upon dispersing pigments in paint vehicles or printing ink varnishes or upon flushing pigments from aqueous filter cakes into oil vehicles or oil varnishes.
Lecithin is however susceptible to oxidation and rancidity and hence involves a potential problem of property changes or rotting, because it is a phospholipid of natural origin. There is thus an outstanding desire for a dispersant or a flushing agent which has better stability and properties than lecithin.